propose backporting a few security fixes to the 2.0.x branch

I haven't properly reviewed/tested these yet myself, but I'd guess
that some among us may be in a good position to review.  (And I
should get to it eventually.)


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.0.x@943603 13f79535-47bb-0310-9956-ffa450edef68